Window fan



FIG. 1 shows a front, top and right side perspective view of a window fan incorporating our new design;

FIG. 2 shows a front elevational view of the window fan shown in FIG. 1;

FIG. 3 shows a right side elevational view of the window fan shown in FIG. 1; the left side elevational view being a mirror image of the right side elevational view;

FIG. 4 shows a top plan view of the window fan shown in FIG. 1; and,

FIG. 5 shows a bottom plan view of the window fan shown in FIG. 1. 

The ornamental design for a window fan, as shown and described. 